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arXiv · 2610.16633

Institutional broadening of the Japanese astronomy and astrophysics research community during 1996-2025

Hideaki Fujiwara
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Abstract

Using bibliometric data from publication records, we investigate the institutional broadening of Japanese astronomy and astrophysics over 1996-2025. The number of Japan-affiliated publications increased from 588 to 2,156, and the number of unique participating Japanese institutions increased from 123 to 227, indicating a nominal broadening of the institutional base. However, institution-publication links remained concentrated among leading institutions, and the effective number of institutions, a frequency-weighted diversity measure, increased more gradually than the number of unique participating institutions. These results show that Japanese astronomy and astrophysics broadened institutionally, but not through a complete equalization of institutional participation. The observed change is best interpreted as an expansion of the participating institutional base around a persistent core of leading institutions.

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Hideaki Fujiwara. 2026-10-12. Institutional broadening of the Japanese astronomy and astrophysics research community during 1996-2025. https://arxiv.org/abs/2610.16633

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